Bolting a Wall Plate to Brickwork for Rafters

[billm]

What type of fixing should I use to bolt a 150x50 wall plate to brickwork to hang single storey pitched roof Rafters off ? Would 100mm long be OK ?

Screwfix have Wall Bolts and Anchors, they look similar but possibly different uses ? I was thinking of using the Bolt type that I could ratchet tight with a socket rather than use a spanner which would leave a thread protruding.

Can you drill through the timber and fix to the bricks all in one go or do you put the fixings in place and then offer the wall plate up to them ?

thanks

 

[noseall]

Sleeve anchors can be knocked in after. We fix our plate with screws first, fit the rafters, then fit sleeve anchors in between the rafters so that the bolts don't clash with the rafter ends etc.

 

[billm]

Thanks, I'll do it that way too.

What depth of Birdsmouth should I cut ? I have read it should be no more than 33% of the rafter depth, so that would be 50mm for a 150mm rafter, although I have seen them much deeper, presumably when they have been struggling to get the right roof pitch.

 

[^woody^]

The cut is as small as possible.

Level across 50mm from the bottom of the plumb cut, plumb down, and that's your notch.

 

[noseall]

What depth of Birdsmouth should I cut ? I have read it should be no more than 33% of the rafter depth, so that would be 50mm for a 150mm rafter, although I have seen them much deeper, presumably when they have been struggling to get the right roof pitch.

We fix the pole/pitching plate with just three fixings.

We then measure the distance from the peak of the pole plate to the edge of the masonry wall plate in several positions. This is because the quirks of lean to roofs means that you are reliant upon the existing walls being plumb, true and not in twist and absent of any sticking out bricks etc - which they are not.

We then make a pattern rafter accordingly. We allow the top notch cut to be deep enough as to allow the rafter plumb cut to travel all the way to the wall. This distance is usually 50mm.

We fit the rafters and secure them to the masonry plate, complete with correct spacings.
We faff around with the pitching plate until we are happy that all the notches are snug. This may mean the odd tweak here and there with a hammer or a pry bar or packers etc. We then fix the rafters to the pole then fix the pole permanently.

It is sometimes easier to fit the rafters then offer the pole up after.

 

[billm]

Thanks lads, all very useful stuff. I've read that some builders put DPC between the pitching plate and the wall, is that standard ?

The rear wall will need 2 Pitching plates because the existing kitchen sticks out 900mm from the Lounge wall. Although I have calculated where the lower plate needs to go on the kitchen wall, practically what I thought of doing is fixing the pitching plate & rafters over the Lounge wall first then fix several battens across the span and offering up the shorter rafters to the battens to see where the pitching plate for the kitchen wall should go ? Hopefully that should agree with my calculations.

The roof will be tiled with Marley Modern or similar, pitch is around 18 deg, I'm not putting any Velux in, and will space the rafters at 400mm centres. Do I need to put any double width rafters in or will it be OK with just singles, and noggins, right across ? The overall width of the extn is approx 6.3m



Is a 50x100mm timber thick enough for over the patio door beam, bolted to it, or do you guys go for 75x100mm ?
thanks

 

[billm]

Are these any good for fixing the Pole plate to the wall ?

http://www.toolstation.com/shop/Scr...chors/sd2792/Fischer+Sleeve+Anchor+FSA/p11582